Pro Audio
Professional Series
IMPERO™ 18A
High power driver recommended for pro audio in vented enclosures. Suited for full-range three-way boxes, bass guitar boxes, and small subwoofers.
| Specification | |
| Nominal Basket Diameter | 18", 457.2mm |
| Nominal Impedance* | 8 ohms |
| Power Rating** | |
| Watts | 1200W |
| Music Program | 2400W |
| Resonance | 33.17Hz |
| Usable Frequency Range | 39Hz - 0.82kHz |
| Sensitivity*** | 95.9dB |
| Magnet Weight | 109 oz. |
| Gap Height | 0.5", 12.7mm |
| Voice Coil Diameter | 4", 101.6mm |
| Thiele & Small Parameters | |
| Resonant Frequency (fs) | 33.17Hz |
| DC Resistance (Re) | 5.41 |
| Coil Inductance (Le) | 1.47mH |
| Mechanical Q (Qms) | 14.02 |
| Electromagnetic Q (Qes) | 0.44 |
| Total Q (Qts) | 0.43 |
| Compliance Equivalent Volume (Vas) | 317.02 liters / 11.19 cu.ft. |
| Peak Diaphragm Displacement Volume (Vd) | 927.2cc |
| Mechanical Compliance of Suspension (Cms) | 0.17mm/N |
| BL Product (BL) | 18.9 T-M |
| Diaphragm Mass Inc. Airload (MMs) | 139.52 grams |
| Efficiency Bandwidth Product (EBP) | 75.37 |
| Maximum Linear Excursion (Xmax) | 8mm |
| Surface Area of Cone (Sd) | 1159 cm2 |
| Maximum Mechanical Limit (Xlim) | 20.1mm |
| Mounting Information | |
| Recommended Enclosure Volume | |
| Sealed | N/a |
| Vented | 113.2-277.5 liters / 4-9.8 cu.ft. |
| Driver Volume Displaced | 409.6 cu.in. / 6.7 liters |
| Overall Diameter | 18", 457.2mm |
| Baffle Hole Diameter | 16.56", 420.62mm |
| Front Sealing Gasket | Fitted as standard |
| Rear Sealing Gasket | Fitted as standard |
| Mounting Holes Diameter | 0.28", 7.1mm |
| Mounting Holes B.C.D. | 17.25", 438.15mm |
| Depth | 8.31", 211.07mm |
| Net Weight | 27.3 lbs, 12.3 kg |
| Shipping Weight | 30.8 lbs, 13.9 kgs |
| Materials of Construction | |
| Coil Construction | Copper voice coil |
| Coil Former | Fiberglass former |
| Magnet Composition | Ferrite magnet |
| Core Details | Bumped Vented Extended core |
| Basket Materials | Die-cast aluminum basket |
| Cone Composition | Water resistant paper cone |
| Cone Edge Composition | Treated cloth cone edge |
| Dust Cap Composition | Water resistant treated paper dust cap |
Footnotes
* Please consult www.eminence.com for specifications of models with alternative impedances.
** Multiple units exceed published rating evaluated under EIA 426A noise source and test standard while in a free-air, nontemperature-controlled environment.
*** The average output across the usable frequency range when applying 1W/1m into the nominal impedance. ie: 2.83 V /8 ohms, 4 V /16 ohms. Eminence response curves are measured under the following conditions: All speakers are tested at 1W/1m using a variety of test set-ups for the appropriate impedance | LMS using 0.25" supplied microphone (software calibrated) mounted 1m from wall/baffle | 2 ft. x 2 ft. baffle is built into the wall with the speaker mounted flush against a steel ring for minimum diffraction | Hafler P1500 Trans-Nova amplifier | 2700 cu. ft. chamber with fiberglass on all six surfaces (three with custom-made wedges).
**** BETA 8CX, 10CX, 12CX and ACOUSTINATOR™ CX 2008 are coaxial speakers with tweeter sold separately. Published Usable Frequency response contingent upon use of APT 50 HF Driver.
***** Multiple units exceeded published rating evaluated under AES 500 and AES 800 noise sources and test standards while mounted on Eminence's TI-2000 horn in a nontemperature-controlled environment.
****** The average on axis output across the entire usable frequency range when applying 1W/1m into the nominal impedance while mounted on a Community SH 494 horn measured with: LMS (software calibrated) using a 0.25" [6.4mm] supplied microphone mounted 1m from horn mouth, Hafler P1500 Trans-Nova amplifier, 2700 cu.ft. chamber w/fiberglass on all six surfaces (three with custom made wedges). Plane-wave tube response and impedance curves measured with LMS on a 0.75" [19.1mm] diameter tube with adapter to allow for smooth transition to throat diameter and 1W/1m into nominal impedance. Prices and Specifications Subject to Change Without Notice.
